using System;

namespace time
{
    public class work_fanxing4
    {
        public static void Main()
        {
            a1(11);
            Console.Read();
        }

        public static void a1<T>(T t1)
        {
            Type tt = typeof(T);
            if (tt.ToString().ToLower().IndexOf("string") != -1)
            {
                Console.WriteLine("is string");
            }
            else
            {
                Console.WriteLine("is not a string");
            }
        }
    }
}